 V. amazonica |
and the Hare Click images to enlarge |
 V. cruziana |
The 2004 hurricanes caused more problems than met the eye, even when we were living their aftermath. For one thing, the 2004 seeds sprouted abysmally after the storms (see What Makes Victoria Seeds Sprout -- or Not, Revisited). For another, not just were our parent plants buried, but so were smaller plants that we had coming along or stalled. For several months we had no time to start more so we began our growing season at a more conventional time, early spring.
This was not a big factor for V. cruziana or the primary hybrids, but it certainly was for V. amazonica! In the winter of 2003-2004, we were very successful carrying as number of plants over the winter as juveniles or graduates (see Survivor Paradise). We got an early start on the 2004 growing season and collected most of our seeds before the storms. We had a good distribution of selfed and crossed species, and of primary and backcross hybrids in hand.
In 2005, the amazonicas lagged far behind the cruzianas in blooming and several didn't bloom at all. The result was few hybrid seeds. Cruziana tends to make its biggest pods fairly early in its bloom period so, by the time we had amazonica for crossing, the cruzianas were in decline. This may well be why breeders in more northerly areas have difficulty making hybrid seeds, something we have hypothesized before.
|
The Tortoise, V. amazonica is a slow grower. This makes sense for an equatorial plant where there is no climatic impetus for rapid growth. Seedlings grow relatively slowly. Adults take their time to come up to size and even more time to bloom. They generally retain size the longest, bloom well into fall in our climate, and last the longest in cold weather. Since they can be perennial in their habitat, it is only our weather that makes them annuals. V. cruziana on the other hand is a fast grower, the Hare, reaching blooming size weeks or months before amazonica in plants of the same age. This also makes sense given the greater climatic swings in its more southerly habitat where it is an annual. Cruziana declines more rapidly than amazonica. It doesn't necessarily die in good weather (though some have) - it just gets small and doesn't produce many seeds. |
 'Adventure' and the cruzianas were shrinking in this late season picture, while amazonica, upper left, was just reaching its full size. |
|
Along the same line, amazonica produces a certain number
of flowers, matures those pods, and then, if the weather is reasonably
good, it will produce another group of blooms. Cruziana
flowers continuously, with the first few flowers often sterile.
Then it makes its big flowers and pods. As the plant shrinks,
pods are smaller and smaller.
Looking back at our growth data, it appears there is little benefit
in early starts for cruziana. By this we mean plants carried
over from the previous year or early fall starts. It may even
be detrimental as several older plants, when installed in previous
years, did not grow as rapidly as younger plants or reach as
large a size. The same may apply to 'Adventure' and 'Longwood
Hybrid' though we have less data on those.
So the trick seems to be to give amazonica a head start, even a year, to stall and hold plants as "graduates", and to get them installed in the pond as early as weather permits. The pattern of spontaneous sprouting seems to parallel this idea, as amazonica germinates fairly well in fall and winter and slows down in spring. This head start for amazonica ought to provide the best chance for the race to be close at the end, with both species flowering at the same time.